Xr/klx mutant motor

[Carlts]

Wow man! SO glad to see it has come together so well. Incredible build man!!!!!

Much respect

 

[The_GDFP]

Haaa. I forgot there was a sweet conversion BIKE involved in the project, too

 

[storminnorman07]

looking good mate..
going by the looks of the clay thickness it looks bigger than 1.6mm clearance tho

it does look like its more than 1.6mm from pic looks like 2~2.5mm but when i put feeler gauges by it and when i used the calipers i was getting about 1.6mm. the clay i used was pretty soft so i may of been smashing it a lil when measuring either way its now in a safe zone so happy

 

[storminnorman07]

Looks amazing! any particular reason you went with the thumb throttle though?

i could give a long story of why i used a thumb throttle but this should sum it up for you

 

[storminnorman07]

Just read this from start to finish ,wow what a build , i love that motor such a credit too ya , do u have an updated video of it running? Didu dyno it yet?

no updated video or dyno yet. just got it together last night. im in the process of looking for a street tire to fit the cr 85 rim but not having much luck. if i can find one and get it here within this week this coming sunday it will get dynoed it not its going to have to wait til next weekend :-(. keep and eye out within the next couple weeks should have a running video and dyno graph of it.

 

[storminnorman07]

Haaa. I forgot there was a sweet conversion BIKE involved in the project, too

lol yeah it was easily over looked with all the talk and bit@hing i was doing with all the complications of the engine.

 

[roost666]

Awesome, LOL at the rear fender sticker with the dude pissing on the pitster pro name

 

[storminnorman07]

well did a lil pissing with it tonight. was doing runs up the street trying to get it tuned in just when it started getting close ole johnny law had to come and piss on my parade and tell me if he catches me on the street again hes hitting me with 4 grand of fines and taken the bike. so i decided i should call it quits. but i took a lil video clip for you guys.

014 - YouTube

 

[storminnorman07]

heres the story. as most know i was having piston problems with my mutant build. i called JE up and talked to them about custom pistons and if they can do it. i spoke with them a number of times on the phone to make certain they can do them. i gave them all the info how i morphed 2 motors bottom end from a xr 80 and top end from a klx and what off the shelf pistons i have used with dimensions. i also had throughly explained how i kept running into exhaust piston to valve clearance and that there was not enough meat in the dome to cut that deep of pockets. That every time i cut a piston i would blow through the dome and had to weld the piston. they assured me they could make a piston to what i needed. so i sent off to them a puck (for those that don't know what that is its a mold of the cylinder and combustion chamber to get relationships for valve centerlines etc..) i also sent a cam doctor readout of cam that would be used, i sent the piston that i cut along with a letter stating what clearances i had with the cut piston and dimensions that would be needed to have appropriate clearances for custom piston. well upon getting custom pistons my ex clearance wasn't enough! now we have been emailing back and forth about the subject. to sum up the emails they went off klx 110 dimensions dont know why cause i told them it was a morphed motor to which i got why would you ever wanna do that. also was told they will not discount or refund these pistons only thing they will do is do another set for me at a fine price of 300 bones and i will have to use rings wrist pin and clips that i already have. which thats another funny story they didnt send all the oil rings for one of the piston sets and price was 120 more than quoted price which they cant explain price difference. last email recieved was snotty and stated they will not tolerate another nasty email from me that they have been professional and are doing their best for me and virtually said i was the one at fault. reason being that cut piston that was sent had a valve notch depth of .050th and they cut custom piston to .157th. well this through the red flag up cause i know i was floating about .155~160ish thousand range on exhaust. so i pulled everything back out and through the calipers on it. low and behold JE's engineers took dimensions from intake side of cut piston thinking it was the exhaust.

below are pics of piston and puck. after the information given if one was have puck and cut piston in their hands would you EVER think the intake side of cut piston was the exhaust? keep in mind i told them about a zillion times i used a off the shelf 2 valve piston. and about 99.99% of the time intake valve will be bigger than the exhaust side correct? so looking at the cut piston you can see factory 2 valve notches one notch is wider than the other side indicating intake. if thats not enough look at second pic the side view of put inline with cut piston. the right side is the exhaust side left side is intake valve angles line up. IF THATS NOT ENOUGH again stated about a billion times about having to weld in the first pic you can see weld markings cause aluminum was so thin. the pic of the bottom of the piston must not of saved but from underside of piston you can see welds cause i didn't pretty them up. so what do you guys think? do you think if i thoughly explained all of the above to you not once but multiple times then handed you a mold of the combustion chamber and a cut pistons that you would EVER mistake the intake side of that cut piston as the exhaust?

JE's exhaust depth

my cut pistons exhaust depth

 

[The_GDFP]

They done screwed ya on that deal. Bastids.

 

[Kurlon]

Everyone's been telling me Carillo is the place to go to for custom pistons, vintage and modern road racers alike seem to think they're the hot stuff. Not that it helps you now.

You could always cast yourself a Torlon piston... I have a friend that makes his own slugs, I could get design / machining pointers from him if you want to go that route?

 

[storminnorman07]

Everyone's been telling me Carillo is the place to go to for custom pistons, vintage and modern road racers alike seem to think they're the hot stuff. Not that it helps you now.

You could always cast yourself a Torlon piston... I have a friend that makes his own slugs, I could get design / machining pointers from him if you want to go that route?

wow havent heard from you in a while where have you been hiding? yeah if your buddy is willing to let go some of his casting secrets i think it would be fun to cast my own piston. but being i have not the slightest clue how to do it makes for alot of secrets to be told

 

[storminnorman07]

so went to go do a break in tune day today, results.....epic fail! weather was total ass cold and raining but was hell bent on getting this bike broke in and tuned for dyno run. got the boys rounded up got to the track got everything unloaded and bikes fired up. while letting the mutant get up to temp before heading back to the track i heard the rpms dropping. so i blipped the throttle and the bottom end sounded tight. i'm like oooo thats not a good sign. so i shut her down and started checking things. fired back up still tight was like chit guys somethings wrong with the crank, not sure what but something is tight. so i called it quits before i hurt something more. went back pulled it back apart yet again! got the head off and to my relief piston looked good no signs of valve contact scoring on cylinder walls or scuffing. as soon as i got jug off i seen the problem. the xr 80/100 has a tin plate on the clutch side of the crank that feeds the big end of the rod. not sure why but for whatever reason that SOB backed it way out. dont know why thought cause it was a new plate fit was super tight but for whatever reason backed out. it ruined that 90 100 dollar ceramic crank bearing and tin sucks but it could of went way worse if the tin completly came out and starved the rod of oil. also a postivie that came out of this is i was def cooking the clutch so clutch springs pressure def needs upped

 

[The_GDFP]

Glad you caught it in time. Under $100, whew.

 

[storminnorman07]

Glad you caught it in time. Under $100, whew.

makes two of us. if i would of ran it anymore and that tin cam out and starved the rod and wreched it o buddy would need a knew offset pin rod prolly would of wiped the cylinder and piston out. i'm pretty sure if it went that way you would of seen different pics posted prolly something along the lines of a big fire and upon close inspection inside inferno you would see a mutant motor. yeah expensive lil buggers thats pretty cheap compaired to some of the full ceramics i was looking at. luckily i have another ceramic bearing sitting here and a new tin. so life is good and since i have apart i order some heavier clutch springs so when they come in it will be up and running again and will have another chance to see what else my bad luck can bring me ;-)

 

[Kurlon]

wow havent heard from you in a while where have you been hiding? yeah if your buddy is willing to let go some of his casting secrets i think it would be fun to cast my own piston. but being i have not the slightest clue how to do it makes for alot of secrets to be told

I've been playing in other circles, picked up full size bike racing, trashed my hand... finally got a mini series locally so I'm poking at it again.

My friend doesn't cast his own, carves them from billet. Casting a plastic (torlon) piston is a whole different ball game, I wouldn't know where to start on that one.

 

[storminnorman07]

I've been playing in other circles, picked up full size bike racing, trashed my hand... finally got a mini series locally so I'm poking at it again.

My friend doesn't cast his own, carves them from billet. Casting a plastic (torlon) piston is a whole different ball game, I wouldn't know where to start on that one.

That sucks the yammy you posted on mmu get ya? Ha ha get back on the "mini" horse again?

Ooo I think I could handle carving billet ;-). 6061 or 7075?

 

[Kurlon]

Been playing with the 1992 WR250R two stroke, pretending I'm a MX 'racer' is heaps of fun. The other Yam project is an FZR400 road racer that's currently an impressive pile of parts... hope to have that done by spring.

In the mean time, can't stay off the 70 for some reason...

 

[storminnorman07]

this should stop that lil bugger from coming out again ;-)

 

[The_GDFP]

Hot glue! That'll do it